1. Amber Release Matti Hiltunen, AT&T
RICAPP project
Amber Release
Matti Hiltunen, AT&T

2. What is an xApp in O-RAN SC Amber Release
Implements a well-defined function
K8s pod with one container
Code written in C++/go/Python
Interacts with the rest of the RIC via AppPaaS libraries
AppPaaS provides:
RMR (RIC Message Router):
Ability to send and receive messages
Message routing determined by the platform
Abstraction layer built on top of NNG
SDL (Shared Data Layer):
Ability to read/write DB and get DB notifications
Abstraction layer built on top of Redis
Logging
File system
xApp
App PaaS
App PaaS
RMR
SDL
logging FS

3. xApps and O1/A1/E2 alignment in Amber
App PaaS
xApps and O1/A1/E2 alignment in Amber
O1: xApp configuration
Configuration exposed to xApp via file system (K8s ConfigMap)
Configuration update can be detected by xApp using iNotify
Agnostic to protocol used for O1
O1 Metrics:
xApp constructs VES event and sends to VES collector
Note: RIC Platform provides Prometheus-based metrics collection and VES reporting.
A1 policy guidance:
xApp receives policy guidance from A1 Mediator via an RMR message with the policy described as a JSON payload. Only AC xApp receives A1 messages.
Pre-spec implementation vs A1 spec:
No separation of policy and policy instance (logically one instance per policy), both create and get operations go to the xApp.
E2:
xApp logically interacts directly with the RAN using E2AP msgs:
Constructs the E2AP ASN.1 message payload and sends it using RMR.
Receives E2AP ASN.1 payload in an RMR message, decodes, and acts on it.
Target RAN element indicated in RMR header.

4. Near Real-Time RIC xApps (RICAPP)
Primary Goals: Support near-real-time radio resource management via development and deployment of a series of xApps that interact with one another and the external components via A1, O1, and E2 interfaces (O-CU/O-DU)
Project Documentation and Coordination
Home:
JIRA:
Meetings:
Project Relations
Near-RT RIC Platform,
Non-RT RIC, OAM
O-CU-CP, O-CU-UP, O-DU
Active participation from AT&T, Samsung
Status
14 Epics defined; 5 Completed; 1 to be moved to RIC platform, 7 in-progress; 0 Blocked; 2 Deferred to Rel B
xApps for Amber:
Admission Control (AC)
Measurement Campaign (MC)
UE Manager
ML-based xApp (Acumos integration)
KPI monitor
References:
Status and Epics :
Applications:
Writing xApps:
ML-based xApps:
JIRA:
Gerrit: